ML19254D070
| ML19254D070 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 09/18/1979 |
| From: | Ippolito T Office of Nuclear Reactor Regulation |
| To: | Dise D NIAGARA MOHAWK POWER CORP. |
| References | |
| NUDOCS 7910220318 | |
| Download: ML19254D070 (3) | |
Text
~
- pa arc UNITED STATES E 7, 3-q [9,h NUCLEAR REGULATORY COMMISSION y
WASHINGTON, D. C. 20555 SEPTEMBER I 81979 Docket No. 50-220 l
Mr. Donald P. Dise Vice President - Engineering Niagara Mohawk Power Corporation l
300 Erie Boulevard West Syracuse, New York 13202 i
i
Dear Mr. Dise:
We are currently reviewing the adequacy of the offsite power systems of nuclear power plants and in particular, the loss of offsite power events at your facility. One aspect of this review concerns the history of experienced total and partial power outages and attendent voltage or frequency conditions of the grid.
In our review of this matter we have drawn upon the infomation provided to us via Licensee Event Reports and followup letters wh'ich you have sent to us. Our review of these reports indicated the loss of offsite power events have occurred at Nine Mile Point on November 17, 1973. To complete our review of loss of offsite power events we require the I
additional infomation concerning the Nine Mile Point offsite grid indicated in the enclosure to this letter.
Please provide your response to the attached questions for Nine Mile Point within 90 days of receipt of this letter.
Sincerely, c
/4 Thoma '. Ippolito, Chief Operating Reactors Branch #3 Division of Operating Reactors
Enclosure:
Request for Additional Infomation cc w/ enclosure:
~
See next page 1194 074 3 IT 7910220 4-
s Mr. Donald P. Dise 2-SDP72!/SER : 8 57; Niagara Mohawk Power Corporation cc:
Eugene B. Thomas, Jr., Esquire LeBoeuf, Lamb, Leiby & MacRae 1757 N Street, N. W.
i Washington, D. C.
20036 j
Anthony Z. Roisman Natural Resources Defense Council 917 15th Street, N. W.
Washington, D. C.
20005 Oswego County Office Building 46 E. Bridge Street Oswego, New York 13126 t
4 9
i O
4 O
O
s 4
REQUEST FOR ADDITIONAL INFORMATION
~
A.
For losses of offsite power where less than all offsite power was lost:
1.
How many circuits to the offsite network are normally available and how many were lost during the event?
2.
What was the cause of the event?
3.
Why did the other lines not fail when some did fail?
4.
Was any voltage increase or decrease experienced just prior to or during the outage?
If so, please give details, voltages reached, affects, etc.
5.
Was any frequency decay experienced just prior to or during the outage?
If so, please give details, lowest frequency reached, decay rate, affects on equipment operation, etc.
6.
How long was power unavailable from the circuit?
7.
Date of Event.
S.
For losses of all offsite power:
1.
How long was the power off? Fow long for partial recovery? Please give details.
2.
If turbine trip occurred, how soon after di.d less of offsite power occur?
3.
If power was recovered promptly (10 minutes or less), was it due to automati:
or manual actions?
4.
Was any voltage increase or decrease experienced just prior to or during the outage?
If so, pleasa give details,' voltages reached, affects, etc.
5.
Was a y frequency decay experienced just prior to or during the outage?
If so, please give details, lowest frequency reached, decay rate, affects on equipment operation, etc.
6.' Date of Event.
C.
Were there any other loss of offsite power events cther than we have listed?
If so, please give details of each event.
8 119407I)
.